delete a list of attributes

[John Miller]

Hi folks,

Thank you very much for your efforts to make pydicom available!

I was wondering if there is a way to feed the del ds.attribute function with a variable, preferably from a list.
The idea is: make a list of attributes, check whether ds includes a certain attribute of that list and if so delete that attribute. (trying to delete an attribute which is not element of the dicom-file caused an error)

[...]
unwanted_attributes = ['ReferringPhysicianName','StudyDescription',etc]
number_of_entries = len(unwanted_attributes)

    for x in range (0,number_of_entries):
        unwanted_attribute = unwanted_attributes[x]
        if unwanted_attribute in ds ==True:
            del ds.unwanted_attribute
[...]

From my understanding the function is searching ds for the literal attribute "unwanted_attribute" which of course is causing an error. I tried different things like del ds.unwanted_attributes[x],... but with no success so far.

Do you have any insight you can share?
Many thanks!
Martin

[Eli Stevens (Gmail)]

You might try delattr(ds, unwanted_attribute), though I'm not certain
if that will work on Dataset objects. del ds[unwanted_attribute] might
also work, not sure.

Aside, you can also structure the loop like so:

for unwanted_attribute in unwanted_attributes:

And skip the len/range/[x] parts.

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[Jonathan Suever]

Either del or delattr will successfully remove the field from the DICOM dataset. Python typically prefers catching an exception to checking explicitly that the field is a member of the dataset. So something like:

for attr in unwanted_attributes:

    try:

        delattr(ds, attr)

    except AttributeError:

        continue

If you want to tackle this in one line I'd go with the following which I think is pretty straightforward:

[delattr(ds, attr) for attr in unwanted_attributes if hasattr(d, attr)]

-Jonathan

[John Miller]

Hi Eli and Suever,

many thanks for your replies. I apologize for my late response, I actually thought my question hasn't been posted after it hasn't shown up after an hour.
I solved it as follows:
    for name in ['some attributes','some more']:
        if name in ds:
            delattr(ds, name)
Probably not as elegant as your solutions, but it works for me.
Again, thank you both for the effort!